The present invention concerns an apparatus for producing and testing a plurality of preferably identical electronic units, in particular in power electronics units.
Apparatuses of that kind, in the form of what are referred to as panels, are generally known from the state of the art for efficiently fitting electronic units or assemblies. More precisely, the panel is a printed circuit board on which, in the respective surface regions thereof, the respective printed circuit board structures are formed for equipping with electronic components for the electronic units; typically such a panel includes between 10 and 30 surface regions arranged in matrix form for identical electronic units which can then be fitted in a common fitting operation in an automatic fitting device (usually the panel makes use of a commercially advantageous fitting surface of an automatic fitting device).
After the fitting or soldering operation, the panel is then divided up, by a procedure whereby the surface regions equipped with components are separated from an unequipped surrounding frame region of the panel (carrier board member), for example by sawing or breaking.
It is then possible in that manner, in one working operation, to efficiently produce a relatively large number of electronic units (which are usually identical), and they are now individually associated with respective casings and then tested or operated in a load mode of operation for a predetermined period of time (burn-in) in order to afford the appropriate functional capability of the respective modules.
Testing and checking devices (often also automated) exist for those burn-in or further functional tests, in which respect conventionally (in otherwise known manner) each electronic unit is provided, as a test piece, with operating voltage signals and further test or load signals; typically, that is effected by means of contact spring pins or the like contact means, which are generally known from the state of the art, in which respect, particularly in the sector of power electronics involving correspondingly high currents which also already have to flow during the burn-in or test phases, it is particularly desirable if a test piece in question is also already provided with suitably equipped plugs or the like contact devices.
Particularly however when dealing with SMD technology and if, for example for reasons relating to design or space, no plug elements have been fitted and soldered in place, the application of operating voltage and load signals for high currents gives rise to problems; burn-in procedures can last for several hours or even days and in the case of voltage transformers or the like electronic units in power electronics, currents of several amperes flow by way of a test contact. That gives rise to correspondingly high demands in terms of the contact quality or minimization of the corresponding contact resistances, as far as the impossibility of true full-load operation, as common external testing systems with contact needles or the like contact elements which can be applied to the test pieces are either a priori not suitable for such current strengths, or however the (necessarily high) contact resistances, with the power levels being contacted, result in a correspondingly great rise in temperature of the arrangement.
A further potential disadvantage of such test procedures, particularly in the area of power electronics, is that contacting with an automatic testing apparatus, for the high currents involved, can typically only be automated with difficulty, or requires a high level of set-up and assembly complication and expenditure so that this also involves a considerable degree of complication (which is detrimental in terms of costs in mass production).
Therefore the object of the present invention is to develop an apparatus for producing electronic units, in particular in regard to their test properties for a high-power or heavy-current sector, to improve the test quality and the practical implementability of tests under full load over a relatively long period of time (or indeed first to permit such) and generally to make the testing of electronic units in power electronics, subsequently to an automated fitting process, more economical, faster and more reliable.
More specifically, in a manner which is advantageous in accordance with the invention, the carrier board member is such that it permits not only the fitment (already generally known from the state of the art) with electronic units in the surface regions respectively associated with an electronic unit, but in addition the carrier board member, by means of the central electrical connecting region which is preferably disposed in edge relationship on the carrier board member and permits cooperation with an external contact plug, affords the possibility of simultaneously feeding operating voltage or load signals to the respective electronic units, in the condition of not yet being separated, so that while still in that condition as an unseparated overall board member, it is possible to carry out a complete functional test in respect of all units. In that respect, it is provided on the one hand for all electronic units to be operated in parallel, but on the other hand there is the possibility of applying individualized signals for each electronic unit as, as can be seen from a preferred development, in particular the load and/or signal lines are provided individually for each electronic unit, are taken out of the central electrical connecting region, and can be actuated separately.
In accordance with the invention that is made possible by virtue of the fact that, outside the surface regions for the actual electronic units, the carrier board member also has conductor tracks provided in the conduction layers, wherein those conductor tracks connect the central electrical connecting region to the conductor tracks in the respective surface regions and for that purpose are also passed by way of the separating regions. In that respect, there is particularly preferably provided in accordance with the invention, for each of the plurality of electronic units in the frame region and in an associated separating region, at least one load and/or signal line which can be individually contacted externally by way of the electrical connecting region and actuation with the operating voltage is effected in any case by way of supply lines. Suitable dimensioning of the respective conduction layers or lines ensures that high currents necessary for full-load tests can also flow, and integration into the common carrier board member always permits optimum contact reliability or signal transmission to the respective component-equipped surface regions as test pieces. Contact problems as occur in particular when using externally applied contact pins of automatic testing apparatuses when high current levels are involved and over test periods of several hours are thus completely eliminated, and also the danger that, for example due to contact problems, units or assemblies which are actually properly functional are wrongly recognized as being defective and are separated off.
In that respect it is particularly preferred for the separating regions to be of such a configuration that on the one hand they still afford sufficient space for passing the conductor tracks to and from the surface regions, while on the other hand facilitating subsequent separation. In an otherwise known manner, it is thought that once again separating procedures using sawing (with suitably rotating saw blades) or by means of a breaking-off procedure can be used for that purpose. In order to facilitate that separation operation, the carrier board member already has suitable slot-shaped openings which already substantially predetermine the contour of the respective surface region and thus the later electronic module.
It is particularly preferable for the carrier board member and accordingly the surface regions to be equipped on both sides; particularly if it is then also in the form of a multi-layer with a plurality of inwardly disposed conductor track layers, it is possible in that way to achieve highly compact arrangements which afford a correspondingly large number of possible ways of testing the arrangement or contacting it for test purposes, in the manner according to the invention, by way of inner layer portions.
It is preferably also provided that a contact frame is fitted on to a component-bearing side; contact frames of that kind can also be easily fitted in the context of the automated component-fitting operation and the automated soldering procedure and then afford a uniform contact surface for later contact purposes.
Accordingly the present invention clearly perceptibly overcomes the disadvantage of automated component-fitting and testing procedures, specifically in the power electronics sector, namely the problem of separate, releasable contacting for testing purposes for high currents and for a long period of time. The problem of existing systems is resolved in a surprisingly simple fashion by the use in accordance with the invention of the frame region surrounding the respective component-fitting surfaces of the electronic modules, for the application, with reliable contact, of supply and signal voltage to the individual units as well as supplying same and carrying same away by means of an individual common plug, without the properties for a subsequent separation operation being adversely influenced thereby.